net/802/fc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * NET3:        Fibre Channel device handling subroutines
   4  *
   5  *              Vineet Abraham <vma@iol.unh.edu>
   6  *              v 1.0 03/22/99
   7  */
   8
   9 #include <linux/uaccess.h>
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/string.h>
  13 #include <linux/mm.h>
  14 #include <linux/socket.h>
  15 #include <linux/in.h>
  16 #include <linux/inet.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/fcdevice.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/errno.h>
  21 #include <linux/timer.h>
  22 #include <linux/net.h>
  23 #include <linux/proc_fs.h>
  24 #include <linux/init.h>
  25 #include <linux/export.h>
  26 #include <net/arp.h>
  27
  28 /*
  29  *      Put the headers on a Fibre Channel packet.
  30  */
  31
  32 static int fc_header(struct sk_buff *skb, struct net_device *dev,
  33                      unsigned short type,
  34                      const void *daddr, const void *saddr, unsigned int len)
  35 {
  36         struct fch_hdr *fch;
  37         int hdr_len;
  38
  39         /*
  40          * Add the 802.2 SNAP header if IP as the IPv4 code calls
  41          * dev->hard_header directly.
  42          */
  43         if (type == ETH_P_IP || type == ETH_P_ARP)
  44         {
  45                 struct fcllc *fcllc;
  46
  47                 hdr_len = sizeof(struct fch_hdr) + sizeof(struct fcllc);
  48                 fch = skb_push(skb, hdr_len);
  49                 fcllc = (struct fcllc *)(fch+1);
  50                 fcllc->dsap = fcllc->ssap = EXTENDED_SAP;
  51                 fcllc->llc = UI_CMD;
  52                 fcllc->protid[0] = fcllc->protid[1] = fcllc->protid[2] = 0x00;
  53                 fcllc->ethertype = htons(type);
  54         }
  55         else
  56         {
  57                 hdr_len = sizeof(struct fch_hdr);
  58                 fch = skb_push(skb, hdr_len);
  59         }
  60
  61         if(saddr)
  62                 memcpy(fch->saddr,saddr,dev->addr_len);
  63         else
  64                 memcpy(fch->saddr,dev->dev_addr,dev->addr_len);
  65
  66         if(daddr)
  67         {
  68                 memcpy(fch->daddr,daddr,dev->addr_len);
  69                 return hdr_len;
  70         }
  71         return -hdr_len;
  72 }
  73
  74 static const struct header_ops fc_header_ops = {
  75         .create  = fc_header,
  76 };
  77
  78 static void fc_setup(struct net_device *dev)
  79 {
  80         dev->header_ops         = &fc_header_ops;
  81         dev->type               = ARPHRD_IEEE802;
  82         dev->hard_header_len    = FC_HLEN;
  83         dev->mtu                = 2024;
  84         dev->addr_len           = FC_ALEN;
  85         dev->tx_queue_len       = 100; /* Long queues on fc */
  86         dev->flags              = IFF_BROADCAST;
  87
  88         memset(dev->broadcast, 0xFF, FC_ALEN);
  89 }
  90
  91 /**
  92  * alloc_fcdev - Register fibre channel device
  93  * @sizeof_priv: Size of additional driver-private structure to be allocated
  94  *      for this fibre channel device
  95  *
  96  * Fill in the fields of the device structure with fibre channel-generic values.
  97  *
  98  * Constructs a new net device, complete with a private data area of
  99  * size @sizeof_priv.  A 32-byte (not bit) alignment is enforced for
 100  * this private data area.
 101  */
 102 struct net_device *alloc_fcdev(int sizeof_priv)
 103 {
 104         return alloc_netdev(sizeof_priv, "fc%d", NET_NAME_UNKNOWN, fc_setup);
 105 }
 106 EXPORT_SYMBOL(alloc_fcdev);